Automatic Generation of Python Class Files

[Bruno Desthuilliers]

Steven Bethard a écrit :
> Bruno Desthuilliers wrote:
> 
>> Steven Bethard a écrit :
>>
>>> Bruno Desthuilliers wrote:
>>>
>>>>> I guess as long as your documentation is clear about which 
>>>>> attributes require computation and which don't...
>>>>
>>>>
>>>> Why should it ?
> 
> [snip]
> 
>> I believe we simply disagree on weither properties should be used when 
>> it makes sens (from a semantic POV, which doesn't prevent common sens, 
>> thanks) or if they should be restricted to refactoring-life-saver. Now 
>> since the second use implies that some attributes-looking properties 
>> of an object may not be what they looks like - and even worth, may 
>> suddenly become (a little bit) more costly without client code being 
>> warned - I don't see what's your problem with the first one.
> 
> 
> I said those kind of expectation violations should be documented, and 
> you said "Why should it?"  I gather you really only meant the "Why 
> should it?" in the situation that the computation is extremely minimal. 

Did you failed to spot some kind of pattern in my previous posts ?-)

More seriously: I do assume that what looks like an attribute will not 
require *heavy* computation - a bit more than 'extremely minimal' is ok 
for me, but we may not have the same definition of 'extremely minimal'. 
And FWIW, I do assume too that computation-heavy functions will be 
either obvious (either from the domain and/or wrt/ what I do pass as 
arguments - ie, I expect that sorting a 10K items list with a custom cmp 
callback will be heavier that naturally sorting a 10 words list) or 
documented as such. Else, I just write my code and, if and when I have a 
real problem, I profile the whole thing...  strange enough, but so far 
it seems to work just fine.

>  I can understand that, but I'd still like it documented for any objects 
> I use.

There are quite a lot of things I'd like to see documented - but 
hopefully I'm mostly working with OSS, so I usually use the source when 
I need a very exact and detailed documentation !-)

Now how does your desire for documentation imply that "if you're 
creating a class for the first time, it should *never* use property()" ? 
I still wonder...

>> Ho, and wrt/ training and expectations, I'm afraid you have to live 
>> with the fact that computed attributes (either properties and custom 
>> descriptors) are alreay widely used. FWIW, may I remind you that a 
>> method is actually a callable returned by a computed attribute ?-)
> 
> 
> Yep.  And it's documented. ;-)

How many Python users ever bothered to read that part of the doc ? How 
many are not even aware of this ?